Sanjeeva
R Guppi
Residence:
1324 Airport Blvd, #47 Grapevine Village
Morgantown, WV 26505
Tel: 304 685 7428
e-mail: sanjeev_ssk@yahoo.com
Graduate Teaching Assistant (August 2002 to April 2004)
Taught for chemistry teaching
labs (CHEM 111, CHEM 115, CHEM 231, CHEM 234, CHEM 233,CHEM 236)
Instructor for Chem 112
Graduate Research
Assistant (May 2004 to Present)
Memberships
Ø
Member of American Chemical Society (ACS)
Ø
Member of International Union of Pure and Applied Chemistry (IUPAC)
Ø
Member of West
Virginia Academy of Science.
Ø
Member of Phi
Lambda Epsilon
Awards
Ø
Outstanding Teaching
Assistant Award for Advanced Organic Chemistry 2004-2005
Ø
Awarded
Eugene Bonnet
Research
Fellowship for terms 2002-03.
Ø
Awarded
Eugene Bonnet
Research
Fellowship for terms 2003-04.
Ø
Awarded
Eugene Bonnet
Research
Fellowship for terms 2004-05.
Ø
Awarded
Eugene
Bennet Research
Fellowship for terms 2005-06.
Asymmetric synthesis of
biologically active compounds (antibiotics, anticancer and anti-HIV) and
development of novel synthetic methodologies.
Publications/Presentations
1. “Synthetic Studies Towards Mannopeptimycin-E: Synthesis of the O-Linked
Tyrosine 1,4-α,α-Manno,Manno-Bis-Pyranoside” Ravula
Satheesh Babu, Sanjeeva R. Guppi
and George A. O’Doherty* Org. Lett., 2006, ASAP
2. “Synthetic studies
towards biologically active Novobiocin Analogues” Sanjeeva
R. Guppi and O’Doherty, G. A. Chem
Tracts-Organic Chemistry, In Press.
3. “De Novo Asymmetric Synthesis of Homoadenosine via a
Palladium-Catalyzed N-Glycosylation Reaction” Sanjeeva R. Guppi, Zhou Maoquan George A. O’Doherty*
Org.
Lett., 2006, 8, 293-296.
5.
Oral Presentation on “De
Novo Approach to Phenyl Glycosides: An Approach to Mannopeptimycin”
S. R. Guppi, R. S. Babu,
and G. A. O’Doherty, at 1st
Midwest Carbohydrate Symposium 2005 at the University of Toledo, Toledo,OH
(Sept.
30th – Oct. 1st 2005)
6.
Poster Presentation on “Synthetic Studies Towards Mannopeptamycins: De
Novo Synthesis of Tyrosine, Serine and Threonine Disaccharides”
S. R. Guppi, R. S. Babu,
and G. A. O’Doherty, at 230th
National ACS Meet at Washington DC (August 28- Sept. 1, 2005).
7.
Oral Presentation on “De Novo Approach to Carbohydrates: Application to
the Synthesis of Oligosaccharides and Mannopeptimycins” R. S. Babu,
S. R. Guppi and G. A. O’Doherty, at 230th
National ACS Meet at Washington DC (August 28- Sept. 1, 2005).
8.
Poster Presentation on "Palladium
catalyzed glycosylation: de novo syntheses of phenol glycosides"
R. S. Babu,
S. R. Guppi and G. A. O’Doherty, at
2005 West Virginia
Academy of Science Meeting (April 23, 2005).
9.
Poster Presentation on “De-Novo Synthesis of Phenol, Flavone and
Coumarin Glycosides” R. S. Babu,
S. R. Guppi and G. A. O’Doherty, at 228th
National ACS Meet at Philadelphia (August 22-26, 2004).
10.
Oral Presentation on “Synthetic Studies of
Mannopeptimycin: De Novo Synthesis of Disaccharide Fragment For Model Study” R. S. Babu, S. R. Guppi and G. A. O’Doherty, at 228th
National ACS Meet at Philadelphia (August 22-26, 2004).
Research
Asymmetric Synthesis of Mannopeptimycin:
Mannopeptimycins 7.1α-ε were isolated from the
fermentation broths of Streptomyces hygroscopicus LL-AC98 and related mutant
strains.7 The key structural features of the Mannopeptimycins are a cyclic
hexapeptide core with alternating D- and L-amino acids, three of which are rare.
Two of the aminoacids (β-hydroxyenuricididine and tyrosine) are glycosylated
with mannose sugars. Among the glycosylated amino acids are an N-glycosylated β-hydroxyenuricididine
with mannose, and an O-glycosylated tyrosine with a α-(1,4-linked)-bis-mannose.
Among the Mannopeptimycins, Mannopeptimycin-ε (7.1ε, Figure 1) was reported as
the most active component against methicillin-resistant staphylococci and
vancomycin-resistant enterococci.
Scheme 7: Synthesis of the disaccharide portion of
Mannopeptimycin.
Enantio-and Diastereoselective Synthesis of Pyranone:
Our de novo approach to
carbohydrates has great potential for preparing various D- and L-sugars because
the starting pyranones can easily be prepared from enantio pure furfuryl
alcohols (either (R) or (S) form) by a two-step procedure (Scheme 2). Depending
on the reaction temperature of the second step, the acylation reaction can
diastereselectively give the α-Boc pyranones 2.1 and 2.5 at –78°C; where as, at
room temperature a 1:1 ratio of the α- and β-Boc protected enones were produced.
Scheme 2: Enantio-and Diastereoselective pyranone synthesis.
De-Novo Synthesis of Phenol, Flavone and Coumarin Glycosides
The natural and unnatural glycosides of phenols, flavones and
coumarins were synthesized using a highly stereoselective and stereospecific
palladium catalyzed glycosylation reaction. To demonstrate the utility of this
procedure coumarin and flavone glycosides were elaborated to their
manno-pyranosides using diastereoselctive reduction and dihydroxylation.
